Grass weeds and volunteers are taking advantage of the persistently wet conditions and difficult, delayed harvest to establish themselves particularly rapidly and robustly this autumn, warns ProCam technical agronomist, Nick Myers.
“Although the scientists tell us black-grass dormancy is high this season, we’re seeing early seedbeds literally heaving with the weed in many cases,” he reports. “The ideal early warm and wet growing conditions appear to have overridden seed dormancy. Either that or we’re seeing last autumn’s very dormant seeds only now germinating.
“At the same time, stubbles are emerging from late-harvested cereals bright green with bindweed, germinating grain, black-grass and, on the headlands, sterile brome. And rape volunteers are making their presence felt wherever harvesting has proved problematic.
“Indeed, weed growth has been so vigorous in some cases that mowing has almost seemed more appropriate than spraying !”
Under these circumstances, Nick Myers urges growers to step-up their stubble and stale seedbed weed control efforts ahead of planting this season if they are to avoid major problems with their winter crops. He sees this as especially important with soil conditions making it so difficult to prepare seedbeds for the greatest pre-em effectiveness, and increasing concerns with post-em treatments.
“Weeds have proved highly problematic for many in the past season,” he points out. “And this autumn seems set to ramp up the pressure even more, with far larger populations of early germinators that are so difficult to control once crops are in the ground. All the more so if pressures to get drilled-up mean growers push ahead without sufficient attention to pre-planting control.
“Regardless of the cultivation regime, the fact that weeds and volunteers are growing so strongly this season means at least one and possibly two, cycles of glyphosate treatment should be feasible without significantly delaying drilling.”
Nick Myers advises growers to treat any green stubbles emerging from harvest with Roundup Max before cultivation, pointing out that rainfastness on annual weeds in just one hour and a cultivation interval of as little as six hours with such modern formulations gives the maximum flexibility under this season’s particular pressures.
Unlike other glyphosates too, he explains that the label allows multiple use in the same application. This keeps open the option of a further spray ahead of drilling if the cultivated ground greens-up again as well as its inclusion in the pre-em mix if time is especially tight.
“I’ve found Roundup Max very useful with pre-em sprays,” he notes. “It’s compatible with most of the commonly used residuals. And by taking out all the weed seedlings germinating in the seedbed as well as those transplanted by cultivations, it makes it much easier to achieve the optimum post-em timing. With early weed growth as rampant as it is this season this will be particularly valuable.
“Your harvest may have been the latest on record and your ground may still be wetter than it has ever been at this time of year, but patience in your autumn fieldwork will still pay dividends,” Nick Myers stresses.
“Taking a few extra days to ensure a decent seedbed will make all the difference to crop establishment as well as both pre-planting and pre-em weed control. After all, October has always been the main season for wheat drilling and the milder autumns and winters we’re definitely seeing these days mean there’s less urgency to drill early. So, above all don’t panic. You’ve got the time to do a good weed control job this autumn. And failing to do so is likely to have serious consequences for both your next crop and your rotation as a whole.”
Cabinet Secretary Sees Harvest Woes First Hand
National Evaluations Prompt 2009 Take-All Alert
Earlier Wheat Harvesting Priority Grows